Glass Round Gems Marbles. No matter what you call them (vase fillers, vase gems, accent gems, flat glass marbles, glass globs, glass shapes, decorative fillers, or flat marbles) decorative glass gems by GVD are one of the most versatile pieces in any crafter kit. These gem stones are eye-catching, it sures bring certain sophistication to whatever they are used with. It can be used as a fillers to hold the stems together in a vase, these gems also make an impressive accessory when sprinkled atop reception tables at weddings.